Meningitis is an acute inflammation of the protective
membranes covering the brain and spinal cord, known collectively
as the meninges
Cause
- Chemical irritation
- Drug allergies
- Fungi
- Parasites
- Tumors
Pathophysiology
Meningococcal meningitis generally has a better prognosis
than septicaemia. Meningococci reach the brain from the bloodstream, implying
that the patient’s immune response has prevented bacterial proliferation in the
blood and not suffered overwhelming sepsis. This is because organisms are
handled differently in these patients, which is probably due to differences in
their inflammatory response to infection as well as different bacterial
characteristics.
Deaths do occur, however due to the severity of the
inflammatory process within the brain.
Once bacteria penetrate the blood-brain barrier, endotoxin
and inflammatory mediators initiate a CSF inflammatory response, causing
leakage of protein and fluid out of the cerebral vasculature. In addition, the
processes delineated in septicaemia occur in brain blood vessels, causing
cerebral oedema and cerebral vascular thrombosis. As a consequence there is an
increase in brain water content and an increase in intracranial pressure. Both
the increased pressure and thrombosis may lead to a reduction in cerebral
perfusion, and consequently cerebral infarction and sometimes brain death.
Sign and symptoms
Bacteria meningitis is an emergency. You will need immediate treatment in a hospital. Symptoms usually come on quickly, and may include:
- Fever and chills
- Mental status changes
- Nausea and vomiting
- Sensitivity to light (photophobia)
- Severe headache
- Stiff neck (meningismus)
Other symptoms that can occur with this disease:
- Agitation
- Bulging fontanelles in babies
- Decreased alertness
- Poor feeding or irritability in children
- Rapid breathing
- Unusual posture, with the head and neck arched backwards (opisthotonos)
Investigstion
- Blood culture
- Chest x-ray
- CT scan of the head
Treatment
Antibiotics are used to treat bacterial meningitis. The specific type depends on which bacteria is causing the infection. Antibiotics do not treat viral meningitis.
Antiviral medicine may be given to those with herpes meningitis.
Other treatments will include:
Fluids through a vein (IV)Antiviral medicine may be given to those with herpes meningitis.
Other treatments will include:
Medicines to treat symptoms such as brain swelling, shock, and seizures
